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27 #ifndef ExecutionContextTask_h
28 #define ExecutionContextTask_h
30 #include "wtf/FastAllocBase.h"
31 #include "wtf/Functional.h"
32 #include "wtf/Noncopyable.h"
33 #include "wtf/PassOwnPtr.h"
34 #include "wtf/text/WTFString.h"
38 class ExecutionContext;
40 class ExecutionContextTask {
41 WTF_MAKE_NONCOPYABLE(ExecutionContextTask);
42 WTF_MAKE_FAST_ALLOCATED;
44 ExecutionContextTask() { }
45 virtual ~ExecutionContextTask() { }
46 virtual void performTask(ExecutionContext*) = 0;
47 // Certain tasks get marked specially so that they aren't discarded, and are executed, when the context is shutting down its message queue.
48 virtual bool isCleanupTask() const { return false; }
49 virtual String taskNameForInstrumentation() const { return String(); }
52 class CallClosureTask final : public ExecutionContextTask {
54 // Do not use |create| other than in createCrossThreadTask and
55 // createSameThreadTask.
56 // See http://crbug.com/390851
57 static PassOwnPtr<CallClosureTask> create(const Closure& closure)
59 return adoptPtr(new CallClosureTask(closure));
61 virtual void performTask(ExecutionContext*) override { m_closure(); }
64 explicit CallClosureTask(const Closure& closure) : m_closure(closure) { }
68 // Create tasks passed within a single thread.
69 // When posting tasks within a thread, use |createSameThreadTask| instead
70 // of using |bind| directly to state explicitly that there is no need to care
71 // about thread safety when posting the task.
72 // When posting tasks across threads, use |createCrossThreadTask|.
73 template<typename FunctionType, typename... P>
74 PassOwnPtr<ExecutionContextTask> createSameThreadTask(
75 FunctionType function, const P&... parameters)
77 return CallClosureTask::create(bind(function, parameters...));